Endangered Species in the Pacific Islands

Hawaiian Picture-wing Flies

Hawaiian picture-wing flies have been called the “birds of paradise” of the insect world because of their spectacular displays during courtship and defense of their territories. Named for their elaborately marked, otherwise clear wings, they belong to the Drosophilidae family of flies.

Hawaiian picture-wing fly
Photo credit Kevin Kaneshiro

Habitat & Behavior:
The 12 species of Hawaiian picture-wing flies protected under the Endangered Species Act are restricted to the Hawaiian Islands. Each species of the 12 Hawaiian picture-wing flies is found only on a single island and the larvae of each are dependant upon only a single or a few related species of plants, some of which are also listed as threatened or endangered. These host plant species are threatened by a variety of factors, including their direct destruction by pigs, goats, cattle, rats, and competition with nonnative plants, and the indirect effects of wildfire and soil disturbance which further promotes the spread of nonnative species into their habitat.

Six species of the picture-wing flies are found on the island of O‘ahu, three on the island of Hawai‘i, and one each on the islands of Kaua‘i, Moloka‘i, and Maui.

Their general life cycle is typical of that of most flies: after mating, females lay eggs from which larvae hatch; as larvae grow they molt through three successive stages; when fully grown, the larvae change into pupae from which they metamorphose and emerge as adults.

Breeding generally occurs year-round and between 50 and 200 eggs are laid in a single clutch. Eggs develop into adults in about a month, and adults generally become sexually mature one month later. Adults generally live at least one to two months.

Past & Present:
All face many threats such as habitat degradation by feral ungulates, loss of host plants, and predation and parasitization by non-native insects including ants and yellow jacket wasps.